From a3ff5fbc94a829680d4aa005cd17add1c1a1fb5b Mon Sep 17 00:00:00 2001 From: Alexander Graf Date: Thu, 27 Jun 2013 01:07:15 +0200 Subject: [PATCH] KVM: PPC: Ignore PIR writes While technically it's legal to write to PIR and have the identifier changed, we don't implement logic to do so because we simply expose vcpu_id to the guest. So instead, let's ignore writes to PIR. This ensures that we don't inject faults into the guest for something the guest is allowed to do. While at it, we cross our fingers hoping that it also doesn't mind that we broke its PIR read values. Signed-off-by: Alexander Graf --- arch/powerpc/kvm/emulate.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/powerpc/kvm/emulate.c b/arch/powerpc/kvm/emulate.c index 631a2650e4e4..2c52ada30775 100644 --- a/arch/powerpc/kvm/emulate.c +++ b/arch/powerpc/kvm/emulate.c @@ -169,6 +169,9 @@ static int kvmppc_emulate_mtspr(struct kvm_vcpu *vcpu, int sprn, int rs) vcpu->arch.shared->sprg3 = spr_val; break; + /* PIR can legally be written, but we ignore it */ + case SPRN_PIR: break; + default: emulated = kvmppc_core_emulate_mtspr(vcpu, sprn, spr_val); -- 2.34.1